Minor fix for sshtest.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2266 ba6dc0ae-232f-0410-883f-9ebac64fc565
SSH: Bug fix for rev 2258.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2267 ba6dc0ae-232f-0410-883f-9ebac64fc565